14 THE DICTIONARY OF GARDENING, 
Actinostrobus—continued. 
densely-branched shrubs, natives of South-western Aus- 
tralia. Flowers moncecious; amenta on very short 
peduncles, or almost sessile, in the axils. Cones ovoid- 
globular or acuminate, the six inner much-enlarged scales 
beconting almost valvate in a single whorl, with six or 
twelve of the outer barren scales more or less enlarged 
and closely appressed or adnate to their base. Leaves in 
whorls of three, very short, thick, rigid and acute, or those 
on the smaller branches appressed, obtuse, and three-angled. 
Only one of the species is known in our gardens. For cul- 
ture see Callitris (to which this genus is closely allied). 
A. pyramidalis (pyramidal). /., amenta one to three lines 
long. cones 4in. in diameter or more. /., lower ones somewhat 
acicular and three to four lines long; those of the main branches 
acute and spreading, din. or less in length ; those on the smaller 
branchlets still shorter, appressed and obtuse. A densely- 
branched, pyramidal, glabrous shrub. 
ACTINOTUS. Syn. Lriocalia. Seven species are 
included in this genus. A. Helianthi is figured in B. R. 
654, and as Eriocalia major in 8. E. B. ii, t. 38. 
ACULEATE HYMENOPTERA. This is a most 
important section of the Order Hymenoptera—an order 
which, judged by the intelligence displayed by the 
majority of its members, should be placed at the head of 
those which go to make up the Class Insecta. The insects 
falling under the above denomination are those which 
bear a sting. Many of them are amongst the most 
familiar of garden insects—Social Bees, Social Wasps, and 
Ants, for instance—and play a very important part in the 
economy of Nature. There are still others inhabiting 
gardens which are more readily passed over, useful 
though they be. Such are the Solitary Wasps, which 
provision their nests with caterpillars (usually of noxious 
species of moths) and spiders. Of these there are no less 
than twenty-nine species in two genera, Humenes and 
Odynerus, mostly inhabiting sandy localities. All are not 
equally common. They are small in comparison with the 
Social Wasps, but prettily banded with yellow on black. 
They are further distinguished by a more or less narrow 
pear-shaped body, and by the tarsal hooks, which are 
simple in the Social and hooked in the Solitary Wasps. 
Aculeate Hymenoptera are thus divided by Mr. S. 
Saunders: Heterogyna, Fossores, Diploptera, and Antho- 
phila. The Heterogyna, or Ants, are insects whose economy 
is fairly well understood, and whose conformation is 
familiar. They are injurious insects to the gardener. The 
Fossores, or diggers, are friends; the insects comprising it 
usually burtow in the sand, and are carnivorous. Some 
species are frequently mistaken for Wasps, though they 
should readily be distinguished therefrom by the disposi- 
tion of the wings, which in Wasps are folded (hence 
Diploptera) longitudinally when at rest; whereas those of 
the Fossores never are. , 
The Diploptera, or Wasps, are further sub-divided into 
Vespide and Eumenide. The former includes the Social 
Wasps, all of which, save the Hornet, are pests to the 
gardener, the good they do being quite discounted by the 
injury to the ripening fruit; and the latter the Sand Wasps, 
all of which are useful to the gardener. 
Another useful. genus in this group is that known 
as Ammophila. These insects have a markedly long 
petiole connecting the abdomen with the other parts of 
the body, and are in» length. from in. to 3in., and 
variously coloured. The long petiole ought, however, to 
distinguish them as friends to the gardener; for like 
their relatives the Solitary Wasps, they furnish their 
nests with caterpillars, &¢c., to feed the larva when 
they hatch out. Then there are others which provision 
them with Aphides, or their near relatives—for instance, 
members of the genera Psen and Mimesa. 
The last section of the Aculeates to be noticed is 
Anthophila. This contains not only the Hive Bee, but 
also many others which are not so well known, or their 
economy so perfectly understood. There are Social Bees 
Aculeate Hymenoptera—continued. 
and Solitary Bees, as there are Social Wasps and Solitary 
Wasps. Some of the Solitary Bees, in particular, are much 
maligned by gardeners and others, and are credited with 
injury they never inflict. Anthidiwm manicatum is a 
case in point. This is a locally distributed insect which 
is popularly supposed to destroy wood by boring into 
it; as a matter of fact this latter is untrue. What the 
Bee really does is to tenant some hole which has 
previously been occupied by another insect, and indus- 
triously line its nest with woolly substances laboriously 
collected from various parts of plants. It is deftly 
rolled up and then carried away. To this section also 
belongs the Corder Bees (certain Bombus species) whose 
nests are built upon the ground, and then carefully 
protected by grass, moss, or what not. These latter 
are Social Bees. 
Other Solitary Bees unfavourably regarded by gardeners 
are the Leaf-Cutters, Megachile cirewmcincta and M. cen- 
tuncularis. Clever insect-architects though they be, and 
undeniably ingenious, 
as they, with unerring 
aim and mathemati- 
cal accuracy, remove 
from Rose-leaves (see 
Fig. 19), or it may 
be from Scarlet Pelar- 
gonium flowers, al- 
most elliptical pieces 
that will fit into the 
required space of 
their nest lining, 
and carry it off, they 
are undesirable in 
gardens. The work 
is always that of the 
female, as the male 
takes no part in the 
provision of a home. 
Usually the insect 
steers clear of the 
midrib of the leaflet, 
but occasionally a 
portion of this also 
is removed. The piece 
of foliage is gra- 
dually detached with 
the insect in position 
on it, though the 
actual severance is 
made while she is on the wing. The whole operation oecu- 
pies but very few seconds; while the pieces removed are 
identical in size, The former is a sand-loying insect, 
and local in its distribution, although in Surrey it may 
be plentifwlly found. For Marechal Niel Rose foliage it 
has a particular affection. The latter is common, and 
occasionally lays the Scarlet Pelargonium flowers under 
contribution to line its nest. 
Fie 19. ROsE FOLIAGE ATTACKED BY 
LEAF-CUTTING BEEs, : 
ADA. These charming orange-scarlet flowered Orchids 
thrive well under similar conditions to that recom- 
mended for Odontoglossum. They do best grown in 
pots, which should be placed within a reasonable distance 
of the roof-glass, where the plants can obtain a liberal 
amount of light anda free cireulation of air whenever 
the outside conditions permit.~ Fibrous peat and living 
sphagnum make a good potting compost. Adas require 
a liberal supply of moisture at the root at all seasons of 
the year. To the species described on p. 22, Vol. I., the 
following should be added: 
A. Lehmanni (Lehmann’s). /l., sepals and petals orange; lip 
white, with a yellow callus. Colombia, 1891. This is distin- 
guished from A. aurantiaca by its white lip, shorter, broader, 
and darker green leaves everywhere marbled with grey, and more 
rigid habit; further, the flowers are produced in the summer. 
